JPH11212672A - Information processor, liquid crystal display device, integrated circuit, wiring board and production of information processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To transmit high-quality signals by eliminating stab wiring to a high- speed and low-amplitude signal such as a differential signal while using a substrate mounting a driver for outputting and transmitting the signals of different electric characteristics such as the signal of single end and the differential signal from one output pin. SOLUTION: Concerning an information processor provided with an input means, control means 2 for stitching the plural kinds of electric signals having different electric characteristics corresponding to modes, transmission line 5 and branched transmission line 6 for respectively receiving the electric signals, and output means, in this case, the branched transmission line 6 has a disconnection/connection setting part 61. As the disconnection/connection setting part 61, a connecting element 71 is mounted or not mounted between terminals, a switching semiconductor element 72 is used and disconnected or connected according to an instruction from the control means 2, and the transmission line 6 is disconnected or not disconnected.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information processing device, a liquid crystal display device, an integrated circuit, a wiring board, and a method of manufacturing an information processing device. The present invention relates to an information processing device that handles a dynamic signal and controls impedance, a liquid crystal display device, an integrated circuit, a wiring board, and a method for manufacturing the information processing device.

[0002]

2. Description of the Related Art In recent years, liquid crystal displays (LCDs)
Not only portable personal computers (PCs) but also desktop personal computers have been used as substitutes for CRT displays in order to save space and power. And the screen size is increasing, and the resolution is also increasing. For this reason, the data transfer speed to the liquid crystal display has been increased, and it has become difficult to transfer data using the conventional signal transfer method.
Thus, a low-amplitude differential transmission system has been used as a system for transmitting a signal at high speed. As shown in FIG. 15A, a differential transmission system is a method of converting one signal into a signal (+ line).
This is a method in which a two-phase signal 24 of a signal 24a and an inverted signal (-line) 24b is generated and transmitted using two signal lines as a pair.
By using this method, data can be transmitted at a high speed with a small amplitude. Further, there is a method of transferring a plurality of pixel data by a pair of differential signal lines, and by using this method, the number of signal lines to the LCD can be reduced. As an example using such a method, there is, for example, a liquid crystal display device described in JP-A-9-16128. Some display LSIs that output differential signals internally switch between a conventional single-ended signal and a differential signal in order to reduce the number of LSI pins.
Some output from the same pin.

Generally, when a system such as a PC is developed, in order to reduce costs and shorten the development period, FIG.
As shown in FIG. 6 and FIG. 17, several models are simultaneously developed by using a common main board on which main components such as a CPU and a display LSI are mounted, and by changing attached devices such as an LCD. Therefore, L corresponding to the conventional single-ended signal
Model 102 with CD and LC for differential signals
When the model 101 with D is developed together, the differential signal connector 3 and the single-ended signal connector 4 are mounted on the main board 1. A conventional connector is used for the single-ended signal connector 4 in order to maintain compatibility with the conventional one, and the differential signal connector 3 has a smaller number of signals and a pair of signal lines compared to the single-ended signal. In order to make them equal in length, a connector 3 dedicated to differential signals is used. For this reason, a conventional display LSI 2 that outputs a single-ended signal and a differential signal from the same pin is used to generate a P signal.
When C is configured, wiring must be performed from one output pin to the differential signal connector 3 and the single-ended signal connector 4, but at this time, as shown in FIG. (Stub) 6 results. When such a stub 6 is generated, a reflected wave is generated at an end point of the stub 6, and a signal may not be transmitted normally. In particular, this has a great effect when a high-speed, small-amplitude differential signal is used.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a circuit board on which a driver for transmitting a signal having a different electrical characteristic such as a single-ended signal and a differential signal from one output pin is mounted. An object of the present invention is to eliminate high-speed and low-amplitude signals such as differential signals by eliminating stub wiring and transmitting high-quality signals.

[0005]

SUMMARY OF THE INVENTION The present invention comprises an input means,
In an information processing apparatus comprising: a control unit that switches a plurality of types of electric signals having different electric characteristics depending on a mode; a transmission line and a branch transmission line each receiving the electric signal; and an output unit; It is an information processing device having a setting unit.

Further, the present invention is the information processing apparatus, wherein the branch transmission line having the above-mentioned cutoff connection setting section is a transmission line for receiving an electric signal having a large signal amplitude or a low transmission speed.

The present invention is an information processing apparatus in which the cutoff connection setting unit is connected when a connection element is mounted between terminals, and is cutoff when not mounted.

Further, the present invention is the information processing device, wherein the connection element is a damping resistor.

Further, the present invention provides the above-mentioned cut-off connection setting unit,
An information processing device that is a switching semiconductor element and that is cut off or connected in response to an instruction from the control unit.

The present invention is an information processing apparatus in which the cutoff connection setting unit is cut off when the branch transmission line is cut, and is connected when the branch transmission line is not cut.

Further, the present invention is the information processing apparatus, wherein the output means is a liquid crystal display.

The present invention also relates to a liquid crystal display device used for the information processing apparatus, comprising a transmission line and a branch transmission line for respectively receiving an electric signal, and the branch transmission line is provided with a cutoff connection setting unit. Is a liquid crystal display device having:

According to the present invention, in a control circuit such as an LSI used as a control means for switching a plurality of types of electric signals having different electric characteristics according to a mode, a cut-off connection setting section of a branch transmission line receiving the electric signal is provided. This is a control circuit such as an LSI having an instructing means for instructing the connection or disconnection.

Further, the present invention is a wiring board used in the information processing apparatus, comprising a transmission line for receiving an electric signal and a branch transmission line, wherein the branch transmission line has a cutoff connection setting unit. It is a wiring board having.

Further, the present invention comprises an input means, a control means for switching a plurality of types of electric signals having different electric characteristics according to a mode, a transmission line and a branch transmission line each receiving the electric signal, and an output means. This is a method for manufacturing an information processing device in which a connection element is mounted on a cutoff connection setting section of a branch transmission line.

The present invention comprises an input means, a control means for switching a plurality of types of electric signals having different electric characteristics according to a mode, a transmission line and a branch transmission line each receiving the electric signal, and an output means. This is a method for manufacturing an information processing apparatus for disconnecting a cutoff connection setting section of a branch transmission line.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described. The present invention is a method for manufacturing an information processing device, a liquid crystal display device, an integrated circuit, a wiring board, and an information processing device,
An information processing apparatus comprising: an input unit; a control unit that switches a plurality of types of electric signals having different electric characteristics according to a mode; a transmission line and a branch transmission line each receiving the electric signal; and an output unit; Has a cutoff connection setting unit. The branch transmission line having the cutoff connection setting unit is a transmission line that receives an electric signal having a large signal amplitude or a low transmission speed. Then, as a cut-off connection setting unit in the wiring board, (1) before connecting the information processing device in the manufacturing process of the wiring board, for example, a connection element, for example, a damping resistor is mounted between the terminals. (2) mounting a switching semiconductor element, and
That is, setting is made so as to be cut off or connected by an instruction from the control means. (3) Setting is made so as to be cut off when the branch transmission line is cut, and to be connected if not cut. An information processing device, a liquid crystal display device, an integrated circuit, a wiring board, and a method for manufacturing an information processing device according to the present invention will be described with reference to the drawings using examples.

The first embodiment will be described with reference to FIGS. Embodiments 1 to 3 are examples in which connection is established when a connection element, for example, a damping resistor, is mounted between terminals, and is cut off when not mounted. The information processing apparatus according to the present embodiment is, similarly to the conventional example, an LVDS (Low Voltage Difference) which is one of the differential transmission systems.
It has a display LSI for switching and outputting between a single signal and a single-ended signal. Then, differences from the conventional example will be described. FIG. 1 shows a wiring board of a liquid crystal display device which is an information processing device of the present embodiment. On the wiring board 1, a display LSI 2, an LVD
S connector 3, single-ended signal connector 4, wiring pattern 5, branch wiring pattern 6, damping resistor 71,
And As the wiring board 1, for example, a thin-film multilayer board is used in which a circuit is formed on a ceramic substrate using Fr4 as an insulating layer and conductive wiring mainly made of copper. Display LSI2
Has a built-in driver for switching and outputting LVDS and single-ended signals depending on the mode, and has an input pin 21 and an output pin 22 and is connected to the wiring pattern 5. The LVDS connector 3 is connected to a wiring pattern 5, while the single-ended signal connector 4 is connected to a branch wiring pattern 6. The wiring pattern 5 is a transmission line and is used as a pair because it is connected to the LVDS connector 3. However, only one wiring pattern is shown in FIG. The branch wiring pattern 6 is a branch transmission line, and is connected to the wiring pattern 5 at a branch point 51 via a cutoff connection setting unit 61. The damping resistor 71 is a resistor required when operating the liquid crystal panel using a single-ended signal, and is about 33Ω. Then, the damping resistor 71 is mounted on the cutoff connection setting unit 61, and at this time, the branch wiring pattern 6 is connected to the wiring pattern 5 at the branch unit 51. If not implemented, it will not be connected. The output driver 23 and the output waveform of the display LSI 2 in this embodiment are the same as in the conventional example, as shown in FIGS. 15A and 15B. The output driver 23 includes a differential signal LVDS 24 and a single-ended signal 2 depending on the mode.
5 and the output is switched. The LVDS performs differential transmission using signals 24a and 24b output from two different output pins 22a and 22b, and transmits data with a smaller amplitude and higher speed than the single-ended signal 25. When the single-ended signal output is used, the damping resistor 71 is mounted on the cut-off connection setting section 61 of the branch wiring pattern 6 as shown in FIG. 1, whereas when the LVDS output is used, it is not mounted as shown in FIG. By doing so, the branch wiring pattern 6 of the wiring pattern 5 can be eliminated at the time of LVDS output without changing the pad on which the component is mounted, and the signal quality can be maintained. Further, since the resistor 71 functions as a damping resistor for reducing overshoot and undershoot of the single-ended signal, the quality of the single-ended signal is also improved.

In the LVDS, actually, a pair 2
Since the signals are transmitted through the signal lines, the wiring patterns 5 of the paired signals are formed in parallel so as to maintain electrical balance as shown in FIG. 3 (only one pair is shown). The branch wiring pattern 6 for transmitting only a single-ended signal may be wired in any way up to the single-ended signal connector 4. For example, when using the wiring board 1 having a two-layer structure or a double-sided mounting, as shown in FIG. 4, a cut-off connection setting part 61 for mounting a resistor 71 and a part 62 of a branch wiring pattern are formed on the back surface of the board. It is also possible to connect to the single-end connector signal connector 4 via the through hole 12 and the branch wiring pattern 6.

In this embodiment, a pair of wiring patterns has been described. However, all the wiring patterns 5 from the output pins 22 at which output signals are switched in all modes are formed in this manner, so that the liquid crystal panel of the LVDS interface can be formed. Necessary signals can be transmitted. In FIG.
5 is an example in which the wiring shown in FIG. 4 is applied to an output pin 22 that switches in all modes. In this example, the branch wiring pattern 6 is formed on the front surface and the back surface of the substrate 1. However, when a substrate having a signal layer also in the inner layer is used, the branch wiring pattern 6 may be formed using the inner signal layer. . In addition, the package of the display LSI 2 may be another package instead of QFP (square planar package).

In this embodiment, the wiring between the display LSI 2 and the connectors 3 and 4 is applied. However, as shown in FIG. 6, the present invention can also be applied to the connection between the display LSI 2 and the receiver ICs 81 and 82. The display LSI 2 having the output pin 22 whose output signal is switched in the mode is connected to the LVDS receiver IC 81 and the single-ended signal receiver IC 82 by the wiring pattern 5 and the branch wiring pattern 6. In the vicinity of the branch point 51 of the branch wiring pattern 6, a cutoff connection setting unit 61 for mounting a resistor 71 on the single-end signal receiver IC 82 side is provided.
When transmitting a single-ended signal to C82, a resistor 71 is mounted on the cutoff connection setting unit 61, and the LVDS receiver I
When transmitting LVDS to C81, the resistor 71 is not mounted. By doing so, the signal quality of the LVDS can be maintained.

Embodiment 2 will be described with reference to FIGS. It is a second example in which a transmission line and a single-ended signal connector are connected by a resistor. On the wiring board 1, a display LSI 2 incorporating a driver for switching and outputting LVDS and single-ended signals according to a mode and an LVDS for connecting to a liquid crystal panel of an LVDS interface.
And a single-ended signal connector 4 for connecting to a single-ended signal interface liquid crystal panel or the like. An output pin 22a whose output signal is switched according to the mode of the display LSI 2 having a built-in driver for switching and outputting the LVDS and the single-ended signal according to the mode is connected to the LVDS connector 3 by the wiring pattern 5. The single-ended signal connector 4 is connected to the wiring pattern 5 via a branch wiring pattern 6 having a cutoff connection setting section 61 on which a resistor 71 is mounted. At the time of LVDS output, it is desirable not to mount the resistor 71 on the cut-off connection setting unit 61 as shown in FIG. 8, but even if it is mounted, the length of the stub can be minimized.
Signal quality can be maintained. As in the first embodiment, the output pin 22 whose output signal switches according to the mode
When all the wiring patterns from a are formed in this way, L
VDS signal quality can be maintained.

Further, although the present embodiment is applied to the wiring between the display LSI 2 and the connectors 3 and 4, it can also be applied to the connection between the display LSI 2 and the receiver ICs 81 and 82 as shown in FIG. The display LSI 2 having the output pin 22 a whose output signal is switched in the mode is connected to the LVDS receiver IC 81 by the wiring pattern 5. On the other hand, the single-ended signal receiver IC 82 and the branch wiring pattern 6
A connection is established by providing a cutoff connection setting unit 61 and mounting a resistor 71. This resistor 71 is not mounted when transmitting LVDS. By doing so, the signal quality of the LVDS can be maintained.

Embodiment 3 will be described with reference to FIGS. 10 and 11. FIG. This is an example of one-stroke wiring. Wiring board 1
Above is a display LSI 2 with a built-in driver that switches and outputs LVDS and single-ended signals according to the mode.
And a connector 3 for connecting a single-ended signal to a liquid crystal panel or the like. The wiring pattern 5 is connected to an output pin 22a whose output signal switches according to the mode of the display LSI 2 having a built-in driver for switching and outputting LVDS and single-ended signals according to the mode.
To the corresponding pin of the connector 3 for the
And to the corresponding pin of the single-ended signal connector 4 via the branch wiring pattern 6. By doing this,
Wiring pattern 5 without stub for LVDS
Can be formed, and the signal quality can be maintained.
LVDS single-ended signal damping resistor 71
By inserting the resistor 71 into the single-ended signal without affecting the LVDS, the resistor 71 can be inserted into the disconnection connection setting section between the connector 3 and the single-ended signal connector 4. FIG. 10 shows the case of one single-ended signal connector 4, while FIG. 11 shows the case of two single-ended signal connectors 4a and 4b. A resistor 71a is provided between the LVDS connector 3 and the single-ended signal connector 4a, and a resistor 71b is provided between the two single-ended signal connectors 4a and 4b. By mounting or not mounting the resistors 71a and 71b, when the branch wiring patterns 6a and 6b are cut off, they do not become stubs.

Embodiment 4 will be described with reference to FIG. This embodiment is an example in which a switching semiconductor element is used. A switching semiconductor element 72 is used instead of the resistor 71 in the first to third embodiments. A display LSI 2 having a driver for switching and outputting between LVDS and a single-ended signal depending on the mode and a driver for outputting an identification signal indicating which of the LVDS and the single-ended signal is being output;
LV to connect to S interface liquid crystal panel
DS connector 3, single-end signal connector 4 for connecting to a single-end signal interface liquid crystal panel or the like, wiring pattern 5, branch wiring pattern 6
And an identification wiring pattern 9. Identification wiring pattern 9
Transmits an identification signal. Switching semiconductor element 72
Can identify the LVDS signal output time and the single-ended signal output time by the identification signal. The switching semiconductor element 72 is turned off when the LVDS signal is output and cut off, and is turned on and connected when the single-ended signal is output. By doing so, it is possible to maintain the signal quality of the LVDS, and it is possible to set the cutoff connection by the control means without performing the work of setting the cutoff connection.

Embodiment 5 will be described with reference to FIGS. 13 and 14. In this embodiment, cutoff or connection is set by cutting or not cutting the branch wiring pattern 6 instead of mounting or not mounting the resistor.
According to the mode, L is placed on the wiring board 1 in this embodiment.
A display LSI 2 incorporating a driver for switching and outputting between VDS and a single-ended signal, an LVDS connector 3 for connecting to a liquid crystal panel of an LVDS interface, and a single-end for connecting to a liquid crystal panel of a single-ended signal interface It includes a signal connector 4, a wiring pattern 5, and a branch wiring pattern 6. In FIG. 13, the branch wiring pattern 6 is not cut. On the other hand, what is shown in FIG. 14 is cut off at the cutoff connection setting unit 62 of the branch wiring pattern 6. Not cutting corresponds to mounting the resistors in the first to third embodiments, and cutting corresponds to not mounting the resistors. By doing so, the signal quality of the LVDS can be maintained. As a cutting method, a physical method such as using a laser or a chemical cutting method such as etching can be employed. In the case of this embodiment, when a damping resistor is used, it may be provided on the branch wiring 6 or the single-ended signal connector 4.

In the first to fifth embodiments, the display LSI
It is possible to insert a resistor, a filter, a capacitor, and the like into the wiring pattern 5 between the connector 2 and the connectors 3 and 4 and the branch wiring pattern 6. In the case where there are a plurality of signal layers in the multilayer substrate, the wiring patterns according to the first to fifth embodiments may be formed in the inner layer to use the through holes.

Next, an example in which the present invention is applied to a personal computer equipped with a liquid crystal panel employing the wiring boards of Examples 1 to 5 will be described with reference to FIG. LVDS PC 101
Has a liquid crystal panel 111 having an LVDS interface, and the single-ended signal personal computer 102 has a liquid crystal panel 112 having a single-ended signal interface. The personal computers 101 and 102 are connected to the same wiring board 1.
With. The wiring board 1 includes a display LSI 2 having a built-in driver for switching and outputting LVDS and single-ended signals according to a mode, and an LVDS connector 3 for connecting to a liquid crystal panel 111 of an LVDS interface.
And a single-ended signal connector 4 for connecting to the single-ended signal interface liquid crystal panel 92.
And make the necessary wiring with the wiring pattern.
In particular, the wiring from the output pin 22 of the driver that switches and outputs the LVDS and the single-ended signal depending on the mode is formed by the wiring pattern shown in FIG. And resistance 7
1 is implemented in the single-ended signal personal computer 102, and L
It is not implemented in the VDS personal computer 101. In this manner, the personal computers 101 and 102 having the liquid crystal panel 111 of the LVDS interface and the liquid crystal panel 112 of the single-end interface are configured using the same wiring board 1 only by mounting or not mounting the resistance of the wiring board 1. can do. Therefore, the development period can be shortened and the cost can be reduced.

The present embodiment is not limited to the case of branching a differential signal and a single-ended signal, but includes an IC having a built-in driver for switching and outputting two types of signals having different electrical characteristics.
It can be applied to an LSI or the like. In this case, at the branch point, a location where a resistor is mounted on the side of the signal where the amplitude is large or the signal is slow by comparing the two types of signals is provided, and the amplitude is large.
Or mount a resistor only when transmitting a slow signal.

[0030]

According to the present invention, a stub is provided by providing a place for mounting a resistor at a branch point of a transmission line on a wiring board on which an IC having pins for outputting signals having different electrical characteristics according to modes is mounted. And the signal quality is improved.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of a wiring board when a single-ended signal is used in a first embodiment.

FIG. 2 is an explanatory diagram of a wiring board when LVDS is used in the first embodiment.

FIG. 3 is an explanatory view of LVDS of the wiring board according to the first embodiment.

FIG. 4 is an explanatory diagram of a modification of the wiring board according to the first embodiment.

FIG. 5 is an explanatory plan view of a modification of the wiring board according to the first embodiment.

FIG. 6 is an explanatory diagram of a wiring board using the receiver IC according to the first embodiment.

FIG. 7 is an explanatory diagram of a wiring board when a single-ended signal is used in the second embodiment.

FIG. 8 is an explanatory diagram of a wiring board when LVDS is used in the second embodiment.

FIG. 9 is an explanatory diagram of a wiring board using a receiver IC according to the second embodiment.

FIG. 10 is an explanatory diagram of a wiring board according to a third embodiment.

FIG. 11 is an explanatory view of a modification of the wiring board according to the third embodiment.

FIG. 12 is an explanatory diagram of a wiring board according to a fourth embodiment.

FIG. 13 is an explanatory diagram of a wiring board when a single-ended signal is used in a fifth embodiment.

FIG. 14 is an explanatory diagram of a wiring board when LVDS is used in the fifth embodiment.

FIG. 15 is an explanatory diagram of single-ended signals, LVDS, and output pins.

FIG. 16 is an explanatory diagram of a conventional wiring board.

FIG. 17 is an explanatory diagram of an information processing device when using LVDS and when using a single-ended signal.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Wiring board 2 Display LSI 21 Input pin 22, 22a Output pin 3 Connector for LVDS 4 Connector for single-end signal 4 5 Transmission line 51 Branch point 6 Branch transmission line 61 Break connection setting part 71 Damping resistor 72 Switching semiconductor element 73 Cutting part 81, 82 Receiver IC 9 Identification transmission line 101, 102 Personal computer 111, 112 Liquid crystal panel

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takeshi Kasai 810 Shimo-Imaizumi, Ebina-shi, Kanagawa Prefecture In-house Systems Division, Hitachi, Ltd. (72) Inventor, etc. 810 Shimo-Imaizumi, Ebina-shi, Kanagawa Hitachi, Ltd. Manufacturing Office System Division

Claims (12)

[Claims] An information processing apparatus comprising: input means; control means for switching a plurality of types of electric signals having different electric characteristics according to modes; transmission lines and branch transmission lines each receiving the electric signals; and output means. The information processing device according to claim 1, wherein the branch transmission line includes a cutoff connection setting unit. 2. The information processing apparatus according to claim 1, wherein the branch transmission line having the cutoff connection setting unit is a transmission line for receiving an electric signal having a large signal amplitude or a low transmission speed. Processing equipment. 3. The information processing apparatus according to claim 1, wherein the cut-off connection setting unit is connected when a connection element is mounted between the terminals, and is cut off when the connection element is not mounted. . 4. The information processing apparatus according to claim 3, wherein said connection element is a damping resistor. 5. The information processing apparatus according to claim 1, wherein the cut-off connection setting unit is a switching semiconductor element, and is turned off or connected by an instruction from the control unit. Information processing device. 6. The information processing apparatus according to claim 1, wherein the cut-off connection setting unit is cut off when the branch transmission line is cut, and is connected when the branch transmission line is not cut. 7. The information processing apparatus according to claim 1, wherein said output means is a liquid crystal display device. 8. A liquid crystal display device used in the information processing device according to claim 1, further comprising a transmission line and a branch transmission line for receiving an electric signal, respectively. A liquid crystal display device, wherein the transmission line has a cutoff connection setting unit. 9. A control means for switching a plurality of types of electric signals having different electric characteristics depending on a mode,
A control circuit for an LSI or the like, comprising: an instruction unit for instructing a cutoff connection setting unit of a branch transmission line that receives the electric signal to be disconnected or connected. 10. A wiring board used for the information processing apparatus according to claim 1, comprising a transmission line and a branch transmission line for receiving an electric signal, respectively.
In addition, the branch transmission line has a cutoff connection setting unit. 11. An input unit, and a control unit that switches a plurality of types of electric signals having different electric characteristics according to a mode.
A method for manufacturing an information processing apparatus comprising: a transmission line and a branch transmission line each receiving the electric signal; and an output unit, wherein a connection element is mounted on a cutoff connection setting unit of the branch transmission line. Device manufacturing method. 12. An input means, and a control means for switching a plurality of types of electric signals having different electric characteristics depending on a mode,
A method for manufacturing an information processing device comprising a transmission line and a branch transmission line each receiving the electric signal, and an output unit, wherein a cut-off connection setting unit of the branch transmission line is disconnected. Method.